[rustc.git] / compiler / rustc_error_codes / src / error_codes / E0714.md

A `#[marker]` trait contained an associated item.

Erroneous code example:

```compile_fail,E0714
#![feature(marker_trait_attr)]
#![feature(associated_type_defaults)]

#[marker]
trait MarkerConst {
    const N: usize; // error!
}

fn main() {}
```

The items of marker traits cannot be overridden, so there's no need to have them
when they cannot be changed per-type anyway. If you wanted them for ergonomic
reasons, consider making an extension trait instead.
Commit	Line	Data
60c5eb7d XL	1	A `#[marker]` trait contained an associated item.
60c5eb7d XL	2
f9f354fc XL	3	Erroneous code example:
	4
	5	```compile_fail,E0714
	6	#![feature(marker_trait_attr)]
	7	#![feature(associated_type_defaults)]
	8
	9	#[marker]
	10	trait MarkerConst {
	11	const N: usize; // error!
	12	}
	13
	14	fn main() {}
	15	```
	16
60c5eb7d	17	The items of marker traits cannot be overridden, so there's no need to have them
9c376795	18	when they cannot be changed per-type anyway. If you wanted them for ergonomic
60c5eb7d	19	reasons, consider making an extension trait instead.